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	<head>
		<title>three.js webgl - 2D compressed texture array</title>
		<meta charset="UTF-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
	</head>
	<script id="vs" type="x-shader/x-vertex">
	uniform vec2 size;
	out vec2 vUv;

	void main() {

		gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );

		// Convert position.xy to 1.0-0.0

		vUv.xy = position.xy / size + 0.5;
		vUv.y = 1.0 - vUv.y; // original data is upside down

	}
	</script>

	<script id="fs" type="x-shader/x-fragment">
	precision highp float;
	precision highp int;
	precision highp sampler2DArray;

	uniform sampler2DArray diffuse;
	in vec2 vUv;
	uniform int depth;

	out vec4 outColor;

	void main() {

		vec4 color = texture( diffuse, vec3( vUv, depth ) );

		// lighten a bit
		outColor = vec4( color.rgb + .2, 1.0 );

	}
	</script>
	<body>
		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - 2D Compressed Texture Array<br />
			Loop from the movie Spirited away
			by the <a href="https://www.ghibli.jp/" target="_blank" rel="noopener">Studio Ghibli</a><br />
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import Stats from 'three/addons/libs/stats.module.js';
			import { KTX2Loader } from 'three/addons/loaders/KTX2Loader.js';

			let camera, scene, mesh, renderer, stats, clock;

			const planeWidth = 50;
			const planeHeight = 25;

			let depthStep = 1;

			init();

			function init() {

				const container = document.createElement( 'div' );
				document.body.appendChild( container );

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 0.1, 2000 );
				camera.position.z = 70;

				scene = new THREE.Scene();

				//
				clock = new THREE.Clock();

				renderer = new THREE.WebGLRenderer();
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				container.appendChild( renderer.domElement );

				//

				const ktx2Loader = new KTX2Loader();
				ktx2Loader.setTranscoderPath( 'jsm/libs/basis/' );
				ktx2Loader.detectSupport( renderer );

				ktx2Loader.load( 'textures/spiritedaway.ktx2', function ( texturearray ) {

					const material = new THREE.ShaderMaterial( {
						uniforms: {
							diffuse: { value: texturearray },
							depth: { value: 55 },
							size: { value: new THREE.Vector2( planeWidth, planeHeight ) }
						},
						vertexShader: document.getElementById( 'vs' ).textContent.trim(),
						fragmentShader: document.getElementById( 'fs' ).textContent.trim(),
						glslVersion: THREE.GLSL3
					} );

					const geometry = new THREE.PlaneGeometry( planeWidth, planeHeight );

					mesh = new THREE.Mesh( geometry, material );

					scene.add( mesh );

				} );


				stats = new Stats();
				container.appendChild( stats.dom );

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function animate() {

				if ( mesh ) {

					const delta = clock.getDelta() * 10;

					depthStep += delta;

					const value = depthStep % 5;

					mesh.material.uniforms[ 'depth' ].value = value;

				}

				render();
				stats.update();

			}

			function render() {

				renderer.render( scene, camera );

			}

		</script>
	</body>
</html>
